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91.
Positive role of macaque cytotoxic T lymphocytes during SIV infection: decrease of cellular viremia and increase of asymptomatic clinical period 总被引:1,自引:0,他引:1
92.
Clinical and Molecular Characterization of Patients with Distal 11q Deletions 总被引:10,自引:0,他引:10 下载免费PDF全文
Laura A. Penny Marie Dell'Aquila Marilyn C. Jones JoAnn Bergoffen Christopher Cunniff Jean-Pierre Fryns Elizabeth Grace John M. Graham Boris Kousseff Teresa Mattina James Syme Lucille Voullaire Leopoldo Zelante Julie Zenger-Hain Oliver W. Jones Glen A. Evans 《American journal of human genetics》1995,56(3):676-683
Jacobsen syndrome is caused by segmental aneusomy for the distal end of the long arm of chromosome 11. Typical features include mild to moderate psychomotor retardation, trigonocephaly, facial dysmorphism, cardiac defects, and thrombocytopenia, though none of these features are invariably present. To define the critical regions responsible for these abnormalities, we studied 17 individuals with de novo terminal deletions of 11q. The patients were characterized in a loss-of-heterozygosity analysis using polymorphic dinucleotide repeats. The breakpoints in the complete two-generation families were localized with an average resolution of 3.9 cM. Eight patients with the largest deletions extending from 11q23.3 to 11qter have breakpoints, between D11S924 and D11S1341. This cytogenetic region accounts for the majority of 11q− patients and may be related to the FRA11B fragile site in 11q23.3. One patient with a small terminal deletion distal to D11S1351 had facial dysmorphism, cardiac defects, and thrombocytopenia, suggesting that the genes responsible for these features may lie distal to D11S1351. Twelve of 15 patients with deletion breakpoints as far distal as D11S1345 had trigonocephaly, while patients with deletions distal to D11S912 did not, suggesting that, if hemizygosity for a single gene is responsible for this dysmorphic feature, the gene may lie distal to D11S1345 and proximal to D11S912. 相似文献
93.
Else Marie Friis Kaj Raunsgaard Pedersen Peter R. Crane 《American journal of botany》1995,82(7):933-943
A new genus and species of fossil angiosperm (Appomattoxia ancistrophora) is established based on well-preserved fruiting units and associated pollen from the Early Cretaceous (Early or Middle Albian) Puddledock locality in the Potomac Group sequence of Virginia, eastern North America. Fruiting units are small, unilocular, and with a single, pendulous, orthotropous seed. The fruit surface is characterized by densely spaced unicellular spines with hooklike tips, which probably functioned in biotic dispersal. Pollen grains adhering to the stigmatic area of many specimens are monocolpate and tectate with granular to columellate infratectal structure, and are similar to dispersed grains assigned to Tucanopollis and Transitoripollis. Comparison of fossil Appomattoxia ancistrophora with extant plants reveals an unusual combination of characters that includes similarities with some magnoliid taxa, particularly Piperales (Piperaceae, Saururaceae) and Laurales (Chloranthaceae), as well as the monotypic ranunculid family Circaeasteraceae. Appomattoxia ancistrophora differs from extant Piperales in having a pendulous rather than erect ovule, and differs from extant Circaeaster in details of the fruit wall, as well as the presence of monosulcate rather than tricolpate pollen. 相似文献
94.
Seven New Mutations in hMSH2, an HNPCC Gene, Identified by Denaturing Gradient-Gel Electrophoresis 总被引:21,自引:3,他引:18 下载免费PDF全文
Juul Wijnen Hans Vasen P. Meera Khan Fred H. Menko Heleen van der Klift Claus van Leeuwen Marianne van den Broek Inge van Leeuwen-Cornelisse Fokko Nagengast Anne Meijers-Heijboer Dick Lindhout Gerrit Griffioen Annemieke Cats Jan Kleibeuker Liliana Varesco Lucio Bertario Marie Luise Bisgaard Jan Mohr Riccardo Fodde 《American journal of human genetics》1995,56(5):1060-1066
Hereditary nonpolyposis colorectal cancer (HNPCC) is a relatively common autosomal dominant cancer-susceptibility condition. The recent isolation of the DNA mismatch repair genes (hMSH2, hMLH1, hPMS1, and hPMS2) responsible for HNPCC has allowed the search for germ-line mutations in affected individuals. In this study we used denaturing gradient-gel electrophoresis to screen for mutations in the hMSH2 gene. Analysis of all the 16 exons of hMSH2, in 34 unrelated HNPCC kindreds, has revealed seven novel pathogenic germ-line mutations resulting in stop codons either directly or through frameshifts. Additionally, nucleotide substitutions giving rise to one missense, two silent, and one useful polymorphism have been identified. The proportion of families in which hMSH2 mutations were found is 21%. Although the spectrum of mutations spread at the hMSH2 gene among HNPCC patients appears extremely heterogeneous, we were not able to establish any correlation between the site of the individual mutations and the corresponding tumor spectrum. Our results indicate that, given the genomic size and organization of the hMSH2 gene and the heterogeneity of its mutation spectrum, a rapid and efficient mutation detection procedure is necessary for routine molecular diagnosis and presymptomatic detection of the disease in a clinical setup. 相似文献
95.
96.
Jacqueline Besson Monique Dussaillant Jean-Claude Marie William Rostene Gabriel Rosselin 《Peptides》1984,5(2):339-340
This paper describes the autoradiographic distribution of VIP binding sites in the rat central nervous system using monoiodinated 123I-labeled VIP. High densities of VIP binding sites are observed in the granular layer of the dorsal dentate gyrus of the hippocampus, the basolateral amygdaloid nucleus, the dorsolateral and median geniculate nuclei of the thalamus as well as in the ventral part of the hypothalamic dorsomedial nucleus. 相似文献
97.
Marie Novak 《International journal for parasitology》1977,7(1):47-50
The number of polycephalic tetrathyridia present in 150-day-old intraperitoneal larval populations of Mesocestoides corti was markedly increased in mice gonadectomized 1 month prior to infection. This effect was more pronounced in male hosts. In both sexes it was inversely correlated with the size of the populations: the smaller the population, the larger was the number of polycephalic tetrathyridia. These forms are probably produced when the separation of daughter individuals lags behind the growth and organogenesis of these peculiar cestodes. 相似文献
98.
André Dupont Lionel Cusan Marie Garon Gabriel Alvarado-Urbina Fernand Labrie 《Life sciences》1977,21(7):907-914
Thirty sec after the intrajugular injection of [3H] methionine-enkephalin (met-enkephalin) in the rat, the radioactivity was already distributed in an apparent volume of 53 ml and the metabolic clearance rate calculated from the characteristics of the plasma disappearance curve was 10 ml/min. As shown by partition chromatography plasma extracts obtained 15 sec after injection of [3H] met-enkephalin, only 5% of the total radioactivity migrated as the intact pentapeptide, while no detectable intact pentapeptide remained 2 min after injection, thus indicating a half-life of [3H] met-enkephalin of the order of 2 to 4 sec. Incubation of rat cerebral tissue with [3H] met-enkephalin indicates that the first step in the breakdown of met-enkephalin in both plasma and brain tissue is cleavage of the Tyr-Gly amide bond. These data offer an explanation for the low activity of met-enkephalin after intraventricular or intravenous administration. 相似文献
99.
Marie Kselíková Tomáš Mařík Bedřich Bíbr Jaroslav Lener 《Biological trace element research》1980,2(1):57-64
This study describes the interaction of molybdenum with blood components. Molybdenum-99 was added to blood, and after four
washings, 3% of the total radioactivity was found in red cells. More specifically, the radioactivity was determined to be
associated with the cell membrane.
Molybdenum-99 in the +VI form did not interact with the human erythrocyte membrane; however, Mo(V) forms did interact. Of
five different compounds, the highes uptake was observed with a brown Mo(V)-ascorbate complex generated from Mo(VI) and ascorbic
acid in the molar ratio 1∶20. A membrane suspension of Mo-ascorbate-treated human erythrocytes was prepared and the solubilized
proteins were separated on a polyacrylamide gel in the presence of sodium dodecyl sulfate (SDS). Molybdenum-99 binding to
spectrin was demonstrated, as well as some minor interactions with membrane hemoglobin and bands 6 and 8. 相似文献
100.
ATP-depleted human red cells have been incubated in a glucose-containing medium with [32P]orthophosphate in the presence and in the absence of cyclic 3',5'-AMP and dibutyril cyclic 3',5'-AMP. Spectrin, pyruvate kinase, phosphofructokinase, glucose-6-phosphate dehydrogenase and hemoglobin A1 have been purified and analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Protein-bound radioactivity has been measured from the sodium dodecyl sulfate polyacrylamide gels and the trichloroacetic acid-precipitated proteins. In the cytosol, the most intense phosphorylation was found for pyruvate kinase whose, in the presence of cyclic AMP, specific radioactivity was comparable to that of the membrane protein and spectrin. In the absence of cyclic nucleotides it was five times less phosphorylated. Phosphofructokinase was only phosphorylated when the red cells were incubated with cyclic nucleotides; the extent of phosphorylation was four times less than for pyruvate kinase. Hemoglobin, glucose-6-phosphate dehydrogenase and a contaminant protein copurified with phosphofructokinase were not phosphorylated: the 'background' of the radioactivity found for these proteins was 100 times less than for pyruvate kinase and spectrin, and 20 times less than for phosphofructokinase (+cyclic AMP). 相似文献